Glass is a kind of amorphous inorganic non-metallic material, generally quartz sand, soda, feldspar as the main raw materials, in addition to a small amount of auxiliary raw materials, through high temperature melting, solidification. The chemical stability, strength and barrier performance of medicinal glass are higher than that of ordinary glass. It is not easy to be broken in the process of drug filling, freeze-drying, high-temperature disinfection and transportation, and it should have strong air-tight barrier performance.
Comparison of performance and applicability of various pharmaceutical packaging materials
| Packaging material | glass | plastic | metal |
| Air permeability | excellent | OK | |
| Air tightness | excellent | It is breathable and permeable | excellent |
| Heat resistance | good ，maximum 450°C, minimum -150°C | poor | good |
| Chemical stability | good | medium | excellent |
| biocompatibility | good | better | excellent |
| strength | crispy | Punctures easily | excellent |
| Energy consumption | Medium (0.3~0.5 tons standard coal/ton glass) | High (5~8 tons of oil/ton of plastic) | higher |
| price | low | high | medium |
The good performance of medicinal glass makes it the preferred material for drug packaging such as antibiotics, general powder, freeze-dried powder, vaccine, blood and biological preparations. According to different glass composition, medicinal glass can be divided into sodium calcium glass, high borosilicate glass, medium borosilicate glass and low borosilicate glass. According to the production process, medicinal glass can be divided into mold bottles and control bottles.
The properties of different kinds of medicinal glass
| species | performance |
| Sodium-calcium glass | Water resistance and thermal shock resistance is poor, generally through the internal surface treatment to improve its stability, but the cleaning process is easy to damage the silicon rich layer on the inner surface to form glass peeling, so the internal surface treatment of sodium-calcium glass bottles are generally suitable for disposable infusion bottles or oral liquid bottles |
| High borosilicate glass | Thermal shock resistance and water resistance are the best (note: the lower the coefficient of thermal expansion is, the better the thermal shock resistance is), but because the transformation process from medicinal glass tube to medicinal glass products requires higher temperature, sealing is more difficult, and it is rarely used as medicinal glass |
|
Neutral Borosilicate glass |
This glass material was invented in 1889 by Short, Germany and gradually promoted. Due to its excellent thermal shock resistance and water resistance, it is used in the packaging of various injections, blood, vaccines and other drugs. It is widely used in the international medical glass material |
| Low borosilicate glass | The impact resistance of borosilicate glass is lower than that of medium borosilicate glass. Although the water resistance of 121°C particles can reach grade 1, the water resistance of its inner surface is weaker than that of medium borosilicate glass. This kind of glass, which was independently developed in the 1960s, can be used to store drugs with low chemical stability requirements (such as ordinary antibiotic injection, oral liquid), but it is difficult to meet the acidic and alkaline drugs |
Comparison of molded bottles and control bottles
| Molded bottle | tubular bottle | |
| technology | The liquid glass is injected into the mold to produce and form, with low difficulty | It is difficult to draw glass tube and then cut glass tube to get glass bottle |
| material | Sodium calcium glass more, can also use borosilicate glass | There are more low borosilicon in China, and mainly middle borosilicon abroad |
| performance | Uneven wall and bottom thickness, poor heat transfer effect, low cost | High strength, stable chemical properties, thin and uniform bottle wall, conducive to heat transfer, high cost |
| application | Large capacity infusion bottle, small capacity injection bottle/celine bottle, oral liquid bottle, medicine bottle | Ampoule, injection bottle, pre-sealed syringe glass tube, oral liquid bottle, medicine bottle |
With the inclusion of injectable consistency evaluation and effective prevention and control of the epidemic, the medicinal glass market in the pharmaceutical packaging industry is expected to accelerate growth. Drug consistency evaluation and related approval are the core driving force to promote the development of glass packaging industry. The Drug Administration requires that the quality and performance of the packaging materials used in injections should not be lower than that of reference preparations, and it is not recommended to use low-borosilicate glass and soda-calcium glass for injections. Therefore, in order to successfully pass the evaluation and approval, pharmaceutical companies will use borosilicate glass to replace the original soda-calcium and low-borosilicate glass packaging materials, thus driving the increase of the demand for traditional Chinese medicine glass in the pharmaceutical packaging industry. According to the data, by 2020, the number of injectable consistency evaluation varieties accepted by CDE continued to increase, and the cumulative number accepted reached 839.
